It is not entirely correct to ask when Cell or RefCell should be used over Box and Rc because these types solve different problems. Indeed, more often than not RefCell is used together with Rc in order to provide mutability with shared ownership. So yes, use cases for Cell and RefCell are entirely dependent on … Read more
Do these effectively give the same result? They are very different. Rc is a pointer with shared ownership while RefCell provides interior mutability. The order in which they are composed makes a big difference to how they can be used. Usually, you compose them as Rc<RefCell<T>>; the whole thing is shared and each shared owner … Read more
Instead of creating a brand new type, you can use Ref::map (since Rust 1.8). This has the same result as Levans’ existing answer: use std::cell::Ref; impl Foo { pub fn get_items(&self) -> Ref<‘_, Vec<i32>> { Ref::map(self.interior.borrow(), |mi| &mi.vec) } } You can also use new features like impl Trait to hide the Ref from the … Read more